The field of the disclosure relates generally to geolocation, and more specifically, to methods and systems for locating an interferer using a satellite system.
Generally, interference geolocation techniques can be grouped into two categories. The first category includes time difference of arrival (TDOA) and/or frequency difference of arrival (FDOA) techniques that use multiple receivers (e.g., satellites). In such techniques, a TDOA signature is determined from two receivers, and an FDOA signature is determined from one of the two receivers and used to locate the interferer. The FDOA signature is created as a result of a Doppler shift between the receiver and the transmitter (i.e., the interferer). Consequently, if the interferer is stationary and the receiver is not moving, there is no FDOA signature created and such techniques do not work. In such scenarios, an additional TDOA signature can be obtained from a third receiver.
The second category of interference geolocation techniques uses array signal processing techniques, such as MUSIC or ESPRIT, to determine an interferer location. These techniques do not use any TDOA or FDOA information. Rather, in such techniques, an array correlation matrix is formed from which the direction-of-arrival information can be obtained. However, generally known array processing techniques require a relatively complex antenna array and associated signal processing components, especially when the number of elements in the array is large.